My EKG, Web of the Electrocardiogram Logo

Corrected QT Interval (QTc) Calculator

To calculate the corrected QT Interval (QTc) enter the duration of the QT Interval (milliseconds) and Heart Rate.

This formula is only valid for Electrocardiograms with Regular Rhythm.

Corrected QT Interval (QTc)

Measure of the QT Interval


Heart Rate


  • Prolonged corrected QT: Greater than 460 ms in children under the age of 15, 450 ms in men, and 470 ms in women.
  • Short QTc Interval: Less than 340ms is accepted as pathological.

How to use the corrected QT Calculator

Enter the measure of the QT Interval (from the beginning of the QRS complex to the end of the T wave) and the Heart Rate of the Electrocardiogram.

Cálculo de QT corregido

Example: Calculate QT Interval, from the beginning of the QRS to the end of the T wave

If you Like it... Share it.